#define _CRT_SECURE_NO_WARNINGS 1

#include <stdio.h>

size_t strLen(const char* str)
{
	const char* begin = str;
	while (*str)
	{
		str++;
	}
	return (size_t)(str - begin);
}

int main()
{
	printf("%d\n", strLen("hello world"));
	return 0;
}